Regulation of glucokinase and GLUT-2 glucose-transporter gene expression in pancreatic B-cells.
نویسندگان
چکیده
Glucokinase (EC 2.7.1.2) is the signal-recognition enzyme in pancreatic B-cells for initiation of glucose-induced insulin secretion. We show here that both the glucokinase and glucose-transporter GLUT-2 genes are regulated physiologically. Fasting decreased B-cell glucokinase and glucose-transporter GLUT-2 mRNA in pancreatic B-cells as well as in liver, whereas refeeding induced expression of both genes. In pancreatic B-cells a approximately 4.4 kb glucokinase-related mRNA was detectable, in addition to the 2.8 kb form. This approximately 4.4 kb glucokinase transcript was drastically decreased during refeeding. The 2.8 kb mRNA, which is typical for pancreatic B-cells, was accompanied after refeeding by a 2.4 kb mRNA species typical for liver glucokinase. Starvation primarily decreased the 2.8 kb pancreatic B-cell glucokinase mRNA species. The concordant regulation of both genes may represent the basis for the physiological regulation of glucose-induced insulin secretion at a transcriptional level.
منابع مشابه
Effects of glucose refeeding and glibenclamide treatment on glucokinase and GLUT2 gene expression in pancreatic B-cells and liver from rats.
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ورودعنوان ژورنال:
- The Biochemical journal
دوره 279 ( Pt 3) شماره
صفحات -
تاریخ انتشار 1991